Chapter 2. Liquid Phase Reactive Sintering of a Complex WCoB-TiC Cermet

  1. Hua-Tay Lin and
  2. Mrityunjay Singh
  1. Adolfredo Sáez1,
  2. Edgar Vidal1 and
  3. Freddy Arenas2

Published Online: 26 MAR 2008

DOI: 10.1002/9780470294741.ch2

26th Annual Conference on Composites, Advanced Ceramics, Materials, and Structures: A: Ceramic Engineering and Science Proceedings, Volume 23, Issue 3

26th Annual Conference on Composites, Advanced Ceramics, Materials, and Structures: A: Ceramic Engineering and Science Proceedings, Volume 23, Issue 3

How to Cite

Sáez, A., Vidal, E. and Arenas, F. (2008) Liquid Phase Reactive Sintering of a Complex WCoB-TiC Cermet, in 26th Annual Conference on Composites, Advanced Ceramics, Materials, and Structures: A: Ceramic Engineering and Science Proceedings, Volume 23, Issue 3 (eds H.-T. Lin and M. Singh), John Wiley & Sons, Inc., Hoboken, NJ, USA. doi: 10.1002/9780470294741.ch2

Author Information

  1. 1

    Department of Materials science. Simón Bolívar University, Sartenejas, PO Box 89000, Caracas 1080. Venezuela

  2. 2

    Department of Materials Technology, University Institute of Technology (IUT-RC), PO Box 40347, Caracas 1040-A. Venezuela

Publication History

  1. Published Online: 26 MAR 2008
  2. Published Print: 1 JAN 2002

ISBN Information

Print ISBN: 9780470375785

Online ISBN: 9780470294741

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Keywords:

  • equimolar mixtures;
  • parameters;
  • micostructure;
  • diffraction;
  • sintering;
  • thermodynamical

Summary

The WCoB is a complex boride that has a very high hardness (45 GPa). In previous works, a very fine coating with a high percentage of this compound has been obtained as a product of surface reaction of pre-sintered samples of WC-Co and WC-Co-TiC with TiB2 or other compounds rich in boron, at 1100d̀C in vacuum. The aim of this work was to promote the formation of the WCoB as a second phase in a bulk by liquid phase reactive sintering of equimolar mixtures of WC and TiB2 with Co varying between 10 - 47 wt%, in order to evaluate its influence on the sintering and formation of WCoB. Sintering was performed in the temperature range: 1400–1600d̀C. The sintered samples were evaluated using SEM, EDX, XRD, EPMA and XPS analyses. It was found that the alloy showing the best properties was that with 18wt% of cobalt which corresponded to a nominal equimolar mixture of WC, TiB2 and Co. The sintered microstructure consisted primarily of WCoB, TiC and some minor quantities of CoB and W2CoB2. A relation between initial Co contents, volume fraction of the different phases formed and mechanical properties is presented.